Strap seal and method of forming the same



Dec. 20, 1932. QTT 1,891,239

STRA? SEAL AND METHOD OF FORMING THE SAME Filed Jan. 23, 1932 2 SheBfi-Sheetb l Dec. 20, 1932. J. E. OTT 1,891,239

STRAP SEAL AND METHOD OF FORMING THE SAME Filed Jan. 23. 1932 2 Sheets-Sheet 2 l 26 i l I ZZ 1 Patented 20, 1932 UNITED STATES PATEN'E crates JOHN EKERN 0T1, OF CHICAGO, ILLINOIS, ASSIGNOR TO ACME STEEL COMPANY, OF

CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS STRAP SEAL AND METHOD OF FORMING THE SAME Application filed Janhary as, 1932. Serial No. 588,317.

This invention relates to strap seals and its purpose is to provide an improved sealing joint for uniting the overlapping ends of a metallic strap such as is commonly employed for reenforcing packages or for securing together a plurality of packages or the like I p that of the strap merely by selecting the most The present invention is an improvement upon the seal joint which is described and claimed in the United States patent to Ralph H. Norton No. 1,260,016, datedMarch 19, 1918.

In said prior patent there is disclosed a strap seal of sleeve-like form through which the overlapping; ends of a metallic strap are threaded and the edges of the strap and seal are then bent and sheared transversely to cause portions of the strap and seal at the edges of the .cuts formed by the shearing action to abut against each other and form an interlocking joint. While a sealof th s type forms a very strong and secure joint, it

has been found in practicethat the strength of the oint is considerably less than that of the steel strap which has its ends secured together by the joint and when a failure has occurred it has uniformly occurred at the joint due to the weakening of the strap at this point. It has been found that the strength of the" binder as a whole maybe increased by decreasing the depth of the cut "or other deformation of the edg s, that is,

the extent to which the out for ed by the shearing action or other deformation extends inwardly froin the lateral edges of the seal and strap but this increase takes place only within certainlimits and a marked decrease is noted as the depth of the cut or other deformationapproaches zero so that the maximum strength which is obtainable by adjusting the depth of the out or deformation to the most suitable proportions, as compared with the Width of the strap, is only 70% or 75% of the strength of the strap. It has also been discovered that some variation in the strength of the joint may be effectedby varying the WidthKOf the cut or other deformation, that is, for example, the distance between two parallel cuts formed by the shearing action, as disclosed in the drawings of said Norton patent, and also that some variation in deformation is most suitable for each widthof thestrap, there is no possibility of increasing the strength of the joint to approximate favorable width or shape of cut or deformation in combination with the most favorable" depth of the cut or deformation.

The present invention obtains the object referred to above by providing a strap and seal with a plurality of separate pairs of deformations formed preferably by separate shearing actions at a plurality of points along the length of the seal and it has been found that by the present invention a strap seal may be obtained which has a strength approximating that of the uncut strap. According to the present invention, the opposite edges of the seal and overlapping ends of the strap are sheared or deformed at a plurality of points along their length to form a plurality of deflected lugs and a pair of interlocking shoulders at the edges of each lug. In practicing this improvement in the formation of a seal joint, the" depth of the cut or deformation inwardly-from the edges of the seal is preferably varied from one side of the deformation to the other so that its inner margin is directed at an angle to the longitudinal axis of the strap. The arrangement of the deformations is alsopreferably such that the angles of the inner margins of some of the deformations are directed oppositely to the angles of the inner margins of the other deformation on" results are ordinarily obtained by increasing the width of each deformation, measured longitudinally of the strap, as the Width of the strap increases. These. and

ends and seal illustrated in Fig.1;

other features of the invention will be more .lappmg ends of a metallic strap uni-Zed by a seal embodying the principles of the present invention and em loying three deformations along each side the seal;

Fig. 2 shows a side elevation of the strap Fig. 3 shows an enlarged transverse section on the line 3-3 of Fig. 1;

Fig. 4 shows a top plan view of another embodiment of the invention, employing four deformations along each side of the seal c Fig. 5 shows a side elevation of the strap ends and seal illustrated in Fig. 4; and

Fig. .6 shows an enlarged transverse sc-' tioh on the line 6-6 of'Fi 4. v v

As illustrated in the rawings, the flat steel strap which ma have been passed around a package and awn taut, for example, is arranged with one end 10 over-. lapping the other end 10" and these overlapping ends are secured together by the strap seal 11 which is in the form of a sleeve 1 rt 1: th 1 nd em 05mg p0 Ions 0 8 over appmg e of the uppermost strap end to overlap the of the strap. This seal may havethe initial form of a sleeve through which the ends 10 and 10 of the stra are threaded or it may have the form of a hannel so that the overlapping ends of the strap may be placedwithin the channel after which the side walls or edge portions 11" of the channel are bent inwardly into contact with one side of the strap as shown, for example, in Fig. 3. The interlocking connection between the ends of the strap 10 and the sleeve 11 is formed by shearing the edges of the strap and seal inwardly at right angles to the length of the strap. According to the present invention, a

plurality of deformations are formed pref- ,erably by a plurality of-pairs of cuts, and in the embodiment illustrated in Figs. 1, 2 and 3 of the drawings, three such pairs of cuts are shown at each side of the seal and strap.

' The shearing of the edges of the strap and seal is preferably efiected by a suitable sealing device having shearing dies for engaging the ed es of the, seal and deflecting portions thereo transversely to form a projecting lug between the cuts of each pair, such, for example, as the sealing device described and claimed in the co-pending application of John Ekern Ott, Serial'No. 588,319, filed.

January 23, 1932. p

In the form illustrated in Figs. 1, 2 and 3. the seal has three pairs of deformations 12 tervenin extending inwardly from the edges of the seal, with the. deformations of each pair located opposite each other. Each deformation 12 is formed by cuttin of the strap and seal inwardly alon two spaced lines 13 and 14 and bending t e inmaterial downwardly to form an intervening deflected lug 15. In forming these deformations, the cuts 13 are preferably made deeper than the cuts 14 so that the inner margin 16 of'the deflected lug or deformation extends at an angle to the longitudinal axis of the strap. The longer cuts 13 of the deformations 12 of each air are located in alignment with each ot er so that the inner margins of the deformations of each pair converge longitudinally of the strap. Where three pairs of deformations are used, it is foundthat the joint has greater strength if the inner margins of the lugs of one pair converge longitudinally in one direction while the inner margins of the lugs of-tlie other two pairs converge longitudinally' in the other direction.

The nature of the interlocking joint which is formed by'the cuts 13 and 14 is shown particularly in Fig. 3, where it will be seen that the formation of the lugs 15 causes the edge portions of the overlapped ends 10 and 10" of the strap to be deflected downwardly along with the looped edge portions of the sleeve 11. The extent of the downward deflection of these ortions of the strap "and seal should preferab y be sufficient to cause the edges edges of the lower strap end and also the or shearing the edges lower wall of the enclosing sleeve and, in

order to obtain this result, it will be apparent pre erably be cut inwardly from the edge of the seal-to a greater extent than the upper from'an examination of Fig. 3 that the lower strag) end and the lower wall of the seal should strap end and the lower wall of the "seal.

This results in the bending of the ed e portions of the seal and of the edge portions of the strap about lines which lie in planes 17 which-are inclined to the surfaces of the seal and'it causes the lugs to have an inclination downwardly toward the cuts 13, longitudinall of the strap, as shown in Fig. 2, in addition to the inclination of their-inner -margins with respect to the longitudinal axis of the strap. The possibility ofobtaining the maximum interlocking effect, that is, the interlockfng of the transverse surface over the maximum area, is increased by increasing the depth of the cuts since the use of deeper cuts permits the edges of the upper strap end be tween :1 pair of cuts to be bent downwardly to such an extent that it overlaps both the lower strap end and the lower-wall of the sea], as shown in Fig. 3. The extent to which the cuts should be extendedinwardly from the edge of the seal should vary directly with the width of the strap and it can bedetervery satisfactory results are obtained in uniting the ends of a two inch strap by means of the present invention if the distance between the inner ends of the cuts 13 is madesubstantially 1-46/64 inches while the distance.

between the inner ends=of the cuts 14 is made 1-51/64 inches. With cuts of this depth and with the inner margins of all of the lugs of all three pairs inclined in the same direction, the joint has a strength of about 84% of that 0 of the uncut strap. l/Vhen the lugs of one pair arereversed, however, so that their inner margins are inclined in a direction opposite to the inclinationof the inner margins of the other two pairs, it is found that the strength of the joint is greatly increased.

For example, with the last-mentioned arrangement of the inner margins of the lugs and with the inner ends of the cuts 13 spaced apart a distance of .1-41/64 inches and with the inner margins of the cuts 14 spaced apart a distance of 1-48/64 inches, it is found-that the joint has a strength of about 94% of the strength of the uncut strap. While the joint between any pair of inwardly extending cuts 13 or 14 may not have a strength acting alone approximating any of the percentages of strength mentioned above, it is found that when a plurality of pairs of cuts are formed in the same seal, the composite strength is greatly increased as compared with that of a single pair of cuts on each side of the strap and this increase is most marked when the inner margins of the lugs of one pair are directed oppositely to the inner margins of the lugs of the other pair. The strength of the joint with one pair of oppositely located lugs or with a plurality of pairs of oppositely located lugs, is increased by making thecuts of unequal depth on opposite sides of each lug, as compared with the strength which would be obtained if these cuts were of equal.

depth. It is therefore possible by means of the present invention to obtain a oint aproximating the strength of the uncut strap by employing a plurality of similar deformations in the edges of the strap seal but, pref erably, with the lugs of one pair directed oppositely to those of the other pairs. By meansofthis invention, therefore, it is possible to reenforce a package or to comb ne a number of packages together by straps which are much smaller in size than those heretofore employed because it has been necessary heretofore to use straps which were large enough to insure the required strength though substantially .at their weakest points, that is, the points where the seals were located and these points have often'only had a strength" of of that of the uncut strap.

In Figs. 4, 5 and 6 of the drawings, there is illustrated a modification of the invention in which the joint is formed by employing four deformations along each edge of the strap and seal. In this embodiment, the strap 20 has one end 20 thereof overlapping the other end 20 and these ends are enclosed by a tubular seal 21. The seal 21 may have the strap ends threaded therethrough or it may be in the form of a channel initially and then have its side walls -21 bent inwardly to overlap the overlapping strap ends, as shown in Fig. 6. In this instance, there are four deformations 22 along each side of the 'seal and each deformation is formed by cutting or shearing the strap and seal transversely along the lines 23 and 24, of unequal depth,

and bending the intervening material downwardly to forma deflected lug 25. As in the form of the inventionlpreviously described,

the cuts 23 are preferably made deeper than the cuts 24 so that the inner margins 26 of the lugs or deformationsare inclined to the longitudinal axis of the strap. The'lugs are located opposite to each other in pairs so that the inclined margins 26 of opposite lugs converge longitudinally of the strap. In'order to obtain the greatest strength, the inner margins of the lugs of twopairs are preferably arranged to converge in a direction opposite to that of the inner margins of the lugs of the other two pairs.

As in the form of the invention first described, the depth of the cuts in the arrange ment shown in Figs..4, 5 and 6, to obtain the best results, will vary directly with the width of the strap. For illustration. it is found that .with the inner margins ofthe lugs of two pairs directed oppositely to the inner margins of the lugs of the other two pairs and with the'inner ends of the Cuts 23 spaced apart a distance of 1-44/64 inches, while the inner ends of the cuts 24 are spaced apart a distance of 1-53/64 inches, the joint has a strength of about 96.8% of that of the uncut strap. Un the other hand, if the inner margins of the lugs are all directed in the same direction, the strength of the joint is considerablyjless than the figures just given, al-

greater than the strengthof a joint made by a-sin'gle pair of oppositely located lugs for a joint using the of unequal depth and of the same cuts on the opposite sides ofeac the cuts on 'the opposite sides'of I claim:

1. A strap seal comprising overlapped strap-ends and a sleeve embracing them, marginal portions of said sleeve and the enclosed strap ends being deflected to form a plurality of similar transversely directed deformations of equal depth along each edge of the sleeve, said deformations having their inner mar= gins inclined to the longitudinal axis of the strap.

2. A strap seal comprising overlapped strap ends and a sleeve embracing them, marginal portions of said sleeve and the enclosed strap ends being deflected to form a larality of similar transversely directed de 01;- mations of equal depth along each edge of the sleeve, said deformations being located oppos'te each other in pairs with the inner margins .of the deformations of each pair converging longitudinally of the strap.

3. A strap seal comprising over lapped strap ends and a sleeve embracing them, marginal portions of said sleeve and the enclosed strap ends being deflected to form a plurality of similar transversely directed deformations of equal depth along each edge of the sleeve, said deformations being located opposite each other'in pairs with'the inner margins of-the deformations of each pair converging longitudinally of the strap, the inner margins of the deformations of-one pair being arranged to converge in a direction opposite .to the on the opposite sides of each lug being of unequal depth and of the same depth as the cuts on the o posite' sides of the other lugs, the depth of each cut increasing progressively from one surface of the seal to the other opposite parallel surface.

strap seal' comprising overlapped strap ends and a sleeve embracing them, the

sleeve and strap ends being provided with spaced cuts extending transversely thereof at the margin of the seal to form an intervening lugywhich is bent transversely to the plane of the strap,the cuts at the opposite edges of said lug being of unequal de t be ri d In testimony whereof, I have an my name.

JOHN EKERN OTT.

convergence of'the inner margins of other 4. A strap seal comprising overlapped strap ends and a sleeve embracing them, marginal portions of the sleeve and enclosed strap ends being sheared transversely of the strap to form along each edge of said'sleeve a plurality of transversely projectin lugs, thelug being of unequal depth and of the same depth as the other lugs. Y

5. A strap seal comprising overlapped strap ends and asleeve embracing them, mar- --ginal portions of the sleeve and enclllsed strap ends being sheared transversely of the strap to form along each edge of said sleeve a plurality of transversely projecting lugs, the cutson the opposite sides of each lug being the cuts on the opposite sides of the other lugs, said lugs being located opposite each other in pairs with the inner margins of the lugs of one pair converging longitudinally of the strap in a direction opposite to the convergence of other opposite lugs formed by said cuts.

6. A strap seal comprising overlapped strap ends and a sleeve embracing them, marginal portions of the sleeve and enclosed strap ends being sheared transversely of the strap to form along each edge of said sleeve a plurality of transversely projecting lugs, thecu ts strap seal comprising overlapped depth as 

